Thermal transfer printing apparatus, method for calibrating thermal transfer printing apparatus, and printing method of thermal transfer printing apparatus

Abstract

A thermal transfer printing apparatus includes a storage to store a plurality of density adjustment parameters that are each associated with a corresponding one of a plurality of first-page calibration patterns and a plurality of second-page calibration patterns, a density adjustment processing part to adjust data on a color gradation value of a first-page superimposing portion and data on a gradation value of a second-page superimposing portion using their respective associated density adjustment parameters, and a printing part to make a print on recording paper to form a plurality of printed calibration patterns that include a printed superimposing portion where the first-page superimposing portion and the second-page superimposing portion are superimposed on each other based on data on color densities adjusted by the density adjustment processing part. A color density of the printed superimposing portion printed on the recording paper varies for each of the printed calibration patterns.

The invention claimed is: 
     
       1. A thermal transfer printing apparatus configured to acquire data on a color of a first image and data on a color of a second image, adjust a portion of the data on the color of the first image thus acquired and a portion of the data on the color of the second image thus acquired using a predetermined density adjustment parameter, and perform a panoramic image printing process of printing the first image and the second image using a plurality of printing surfaces arranged on an ink sheet to cause the portion of the first image thus adjusted and the portion of the second image thus adjusted to be superimposed on each other, the thermal transfer printing apparatus comprising:
 a divided image data receiver to acquire data representing a first-page calibration image including data on a color density of a plurality of first-page calibration patterns and data representing a second-page calibration image including data on a color density of a plurality of second-page calibration patterns; 
 a calibration-use density adjustment parameter storage to store a plurality of the density adjustment parameters that are each associated with a corresponding one of the plurality of first-page calibration patterns and the plurality of second-page calibration patterns; 
 processing circuitry to execute a density adjustment processing to adjust data on a color density of a first-page superimposing portion that is superimposed on a corresponding one of the plurality of second-page calibration patterns during printing of the data on the color density of the plurality of first-page calibration patterns using one of the density adjustment parameters associated with a corresponding one of the first-page calibration patterns and adjust data on a color density of a second-page superimposing portion that is superimposed on a corresponding one of the plurality of first-page calibration patterns during printing of the data on the color density of the plurality of second-page calibration patterns using one of the plurality of density adjustment parameters associated with a corresponding one of the second-page calibration patterns; and 
 a printer to print the first-page calibration image and the second-page calibration image on recording paper to form a plurality of printed calibration patterns that are each constituted by one of the first-page calibration patterns and one of the second-page calibration patterns and include a printed superimposing portion where the first-page superimposing portion and the second-page superimposing portion are superimposed on each other based on the data on the color densities adjusted by the density adjustment processing, wherein 
 a color density of the printed superimposing portion printed on the recording paper varies for each of the printed calibration patterns. 
 
     
     
       2. The thermal transfer printing apparatus according to  claim 1  further comprising a calibration pattern selection receiver to receive a signal including data on the printed calibration pattern selected from among the plurality of printed calibration patterns that have been printed, wherein
 the density adjustment parameters associated with the first-page calibration pattern and the second-page calibration pattern constituting the printed calibration pattern thus selected are used in the panoramic image printing process. 
 
     
     
       3. The thermal transfer printing apparatus according to  claim 1 , wherein
 the printer makes a print to cause a color density of each of the printed calibration patterns in a primary scanning direction to increase stepwise from one end to an other end in the primary scanning direction. 
 
     
     
       4. The thermal transfer printing apparatus according to  claim 3 , wherein
 the data on the color density of each of the first-page calibration patterns and the data on the color density of each of the second-page calibration patterns acquired by the divided image data receiver are each set to cause a corresponding density to increase stepwise from one end to an other end in the primary scanning direction. 
 
     
     
       5. The thermal transfer printing apparatus according to  claim 1 , wherein
 the data on the color density of each of the first-page calibration patterns and the data on the color density of each of the second-page calibration patterns each represent a gradation value of a pixel to which line numbers are assigned in the primary scanning direction and a sub-scanning direction, 
 the plurality of the density adjustment parameters each represent a predetermined density adjustment factor associated with the line number of the pixel in the sub-scanning direction, and 
 the density adjustment processing adjusts the gradation value of the pixel associated with the density adjustment factor based on the density adjustment factor. 
 
     
     
       6. The thermal transfer printing apparatus according to  claim 1 , wherein
 the printer prints the first-page calibration image using a portion of one of the printing surfaces, and prints the second-page calibration image using an other portion of the printing surface used for printing the first-page calibration image. 
 
     
     
       7. The thermal transfer printing apparatus according to  claim 1 , wherein
 each of the printed calibration patterns includes a non-superimposing portion where the first-page calibration patterns and the second-page calibration patterns are not superimposed on each other. 
 
     
     
       8. A method for calibrating a thermal transfer printing apparatus comprising:
 acquiring data representing a first-page calibration image including data on a color density of a plurality of first-page calibration patterns and data representing a second-page calibration image including data on a color density of a plurality of second-page calibration patterns; 
 adjusting data on a color density of a first-page superimposing portion that is superimposed on a corresponding one of the plurality of second-page calibration patterns during printing of the data on the color density of the plurality of first-page calibration patterns thus acquired using a density adjustment parameter associated with a corresponding one of the plurality of first-page calibration patterns and adjusting data on a color density of a second-page superimposing portion that is superimposed on a corresponding one of the plurality of first-page calibration patterns during printing of the data on the color density of the plurality of second-page calibration patterns thus acquired using a density adjustment parameter associated with a corresponding one of the plurality of second-page calibration patterns; 
 printing the first-page calibration image and the second-page calibration image on recording paper to form a plurality of printed calibration patterns that are each constituted by one of the first-page calibration patterns and one of the second-page calibration patterns and include a printed superimposing portion where the first-page superimposing portion and the second-page superimposing portion are superimposed on each other based on the data on the color densities thus adjusted and to make a color density of the printed superimposing portion different for each of the printed calibration patterns; 
 receiving a signal including data on the printed calibration pattern selected from among the plurality of printed calibration patterns printed on the recording paper; and 
 storing, in a density adjustment parameter storage, the density adjustment parameters that are each associated with a corresponding one of the first-page calibration patterns and the second-page calibration patterns constituting the printed calibration pattern thus selected. 
 
     
     
       9. A printing method of a thermal transfer printing apparatus comprising:
 acquiring data on a color of a first image and a color of a second image; 
 adjusting a portion of the data on the color of the first image thus acquired and a portion of the data on the color of the second image thus acquired using the density adjustment parameters stored in the density adjustment parameter storage in the method for calibrating a thermal transfer printing apparatus according to  claim 8 ; and 
 printing the first image and the second image using a plurality of printing surfaces arranged on an ink sheet to cause the portion of the first image thus adjusted and the portion of the second image thus adjusted to be superimposed on each other.